O2 sensor mystery?

[UKStangGT]

Ever since I fitted the Magnflow catted X-pipe the CEL has been on, Im getting code P1131, lean on bank #1, Ive read everywhere that I need MIL eliminators on the downstream sensors, the thing is I dont have downstream sensors, the car has never had them, at the moment I have swapped the sensors from left to right and am waiting for the CEL to light again, hoping it will show on the other bank, Am I the only 1 with no downstream sensors, all the SN95's in the UK have them. Any ideas? :angel4:

 

[SRT Handz]

It sounds to me like you need to buy new upstream o2 sensors.

 

[Willis_98GT]

It sounds to me like you need to buy new upstream o2 sensors.

+1, start with a cleaning, unless your thinking its tune time.

 

[UKStangGT]

The CEL came back with P1151, same fault on the other bank, getting new O2 sensors tomorrow :headbang:

 

[SRT Handz]

ONLY buy the Ford 02 Sensors. Records have shown the other brands fail very fast on these cars.